The first big blockbuster of the summer, Wonder Woman, sees Diana leave the island home of the Amazon to end “the war to end all wars.”
So Wonder Woman goes into battle not only against mythological forces of evil, but early 20th-century weapons like poison gas, airplanes and machine guns.
In the film a dastardly Hun general believes his super poisonous gas will strike a fatal blow to the British. In fact, poison gas was one of the defining weapons of the First World War. German and Allied forces fought to a stalemate in the trenches, and it took the creativity of scientists and engineers to come up with even more horrific forms of weaponry. Initial attempts at gas warfare were a bit feeble, but by April, 1915, the Germans had 150 tons of chlorine gas that they deployed to devastating effect against the French at Ypres. Counterattacking Canadian forces met an even bigger attack the next day, and as many as 5000 were killed, with countless more seriously wounded.
The German army wanted an even more lethal gas that could be delivered by artillery, which led to the development of phosgene. While it destroyed the lungs and stopped suffocating soldiers in their tracks, it was not as well known as the mustard gas that features in Wonder Woman. Although much less deadly with a 2% mortality rate, mustard gas disabled anyone inside the cloud. Moreover, it caused the skin to blister as well. The film features a super-mustard gas made with hydrogen that burns through gas masks. While that is a fabrication, the Germans did in fact learn how to disable gas masks.
They mixed chlorine with a chloro-formate tear gas. The filters in the masks blocked the chlorine, but not the tear gas. It built up inside the mask until the level became unbearable. The victim would rip off the mask only to be done in by the chlorine.
For more information on Wonder Woman, please read:
The Real Story of the World War I Poison Gas in ‘Wonder Woman’ | Popular Mechanics